Electromagnetic reversing contactor with interlock



March 25, 1958 J. E. DAVIES ETAL 2,828,381

ELECTROMAGNETIC REVERSING CONTACTOR WITH INTERLOCK Filed Oct. 7, 1955 2 Sheets-Sheet l @mvVov/z.

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Mafch 1953 J. E. DAVIES EIAL 2,828,381

ELECTROMAGNETIC REVERSING CONTACTOR WITH INTERLOCK Filed Oct. 7, 1955 2 Sheets-Sheet 2 United States Patent ELECTROMAGNETIC REVERSING CONTACTOR WITH INTERLOCK James E. Davies, Granville, and Robert W. Siebers, Milwaukee, Wis., and Charles W. Otto, De Kalb, Ill., essignors to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware Application October 7, 1955, Serial No. 539,174

6 Claims. (Cl. 200-87) This invention relates to a hermetically sealed reversing type of electromagnetic contactor with interlock.

In the Davies and Otto application Serial No. 403,124, filed January 11, 1954, there is disclosed an improved type of hermetically sealed contactor. It is an object of the present invention to provide improved hermetically sealed reversing type of electromagnetic contactors which are built-up from a pair of like contaetors of the type disclosed in the aforementioned application.

Another more specific object is to provide a novel form of mechanical interlock for a reversing contactor of the aforementioned type which greatly facilitates assembly of the reversing contactor and provides for ready adjustment of interlock prior to final assembly.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate a preferred form of the invention which will now be described in detail, it being understood that the embodiment illustrated is susceptible of various modifications in respect of details without departing from the scope of the appended claims.

In the drawings:

Figure l is a plan view of a hermetically sealed reversing type electromagnetic contactor constructed in accordance with the invention;

Fig.2 is a fragmentary view to larger scale and partially in section, which illustrates internal details of the contacts.

Fig. 3 is a view taken along the line 3--3 of Fig. 2.

Fig. 4 is a sectional View taken along the line 44 of Fig. 2.

Fig. 5 is a view taken along the line 5-5 of Fig. 2, and

Fig. 6 is a view similar to Fig. 5, but depicting an intermediate state of assembly of certain parts.

Referring to Figs. 1 and 2, they show a hermetically sealed electromagnetic cqpt ictor of the reversing type which comprises the contactor units A and B, which are like contactors shown and described in the aforementioned Davies and Otto application. More particularly each of the contactor units comprises a housing, which includes a substantially rectangular cup-shaped member 15 in which is housed the contactor assembly, and a closed end, cylindrical cup-shaped member 16 in which is housed a solenoid operating assembly. In final assembled state the corresponding flanged end edges of the walls of the members 15 of units A and B are welded together about their periphery to join the same in a hermetic seal along the joint designated 17. Thus, the contactor assemblies and solenoid operating assemblies of the two units are disposed in opposed axial relation. Bracket 18 mechanically fastened, as by welding, to the outer wall of the member 18 of each unit A and B facilitates mounting of the contactor to a Wall or panel.

The details of the contactor assemblies, solenoid operating assemblies, terminal arrangement for each of the contactor units A and B are exactly like those shown in the aforementioned Davies and Otto application to which reference should be made. Thus detailed description of those parts and assemblies will be dispensed with in the present application for the sake of simplicity.

The solenoid operating asemblies of units A and B are mechanically interlocked by means of an assembly generally designated 19. Assembly 19 comprises a collar 29, a locking washer 21, anadjusting nut 22, a spring clip 23, a washer 24, a nut 25 and a C-shaped washer 26. In assembling unit A, locking washer 21 is inserted over the reduced threaded end portion 27 of a pin 27, which at its other end has a drive fit within a solenoid operating plunger 28 of unit A, thus forming an extension of such plunger. The key lug 21 of the washer 21 fits within a keyway 27 of the pin, and such washer bears against a pressure spring 29 which bears at its other end against the center contact carrier 30 of the contactor as sembly. Adjusting nut 22, which is generally of circular disc form, has a central threaded opening 22 by means of which it is screwed down on the portion 27 of pin 27.

Nut 22 is screwed down on pin 27 until the desired spring pressure is established and then is locked into non-rotatable engagement with a pair of diametrically opposite lugs 21 of washer 21 engaging within complemental openings 22 formed in nut 22. There are six such openings 22 formed in the nut which are spaced at equal rotary angles of 60, thus permitting locking of the nut with washer 21 in any 60 increment of rotary adjustment. Then, collar 20, which has an internally threaded cylindrical portion 29 is screwed on to the outer peripheral threaded portion 22 of nut 22. When the final adjustment of collar 20 on nut 22 is neared, a pair of longitudinal slots 20 which are spaced circumferentially at an angle of 60 are brought into registration with two radial recesses 22 formed in the periphery of nut 22. Six such recesses 22. are formed at equal rotary angles of 60 thus permitting such registration for each 60 increment of collar rotation on nut 22. Then the inturned ends 23*- of spring clip 23 are inserted through the slots 20 and seated in the recesses 22 thereby locking the collar 20 in adjusted position on nut 22.

In assembling unit B, the washer 24 which has a shallow elongated depressed portion 24 a circular flanged portion 24 and a key lug 24 is inserted over the portion 27 of the pin 27 and seated on the lower surface of its depressed portion 24 against the pressure spring 29. Then a hexagonal nut 25 is screwed down on the portion 27 of the pin and is locked into position by seating within the depressed portion 24 of the washer. The inside width across the short dimension of the depressed portion 24 is such as to permit the nut to seat in any one of six rotary positions and hold it against rotation when so seated.

In the final assembly of the contactors, the open ends of the cup member 15 of units A and B are disposed towards each other, but slightly offset to one side. Then, with their flanged end edges almost in engagement they are brought into axial alinement in such a manner that the Washer 24 of unit B freely slides into a cut-away notch 20 formed in the lower cylindrical segment portion 20 of collar 20 (see Fig. 6) above the C-shaped washer 26 which seats against and is brazed in place on a shoulder formed in the portion 20 Then the edges of the cup members 15 are exactly matched and welded together to provide the hermetically sealed joint 17. The interior of the units are then evacuated through an opening 35 formed in member 15 of unit A, and after a desired inert atmosphere has been introduced into the unit the opening 35 is sealed by a welded plug 36.

As shown in Fig. 1, in the completely deenergized state of the reversing contactor, clearance will exist between th lower surface of the flanged portion 24 of Washer 24 and the upper surface of C-shaped washer 26. This clearance, which is established by the adjustment of collar 20 n nut 22, is determined by the stroke of the solenoid plunger of the unit which is the greater of the two, plus addition of approximately .085 of an inch. Thus with the solenoid operating coil of one of the units energized, the closed gap between portion 24 and washer as will be a few thousandths of an inch. Thus, for example, if solenoid operating coil of unit A is energized, the contactor assembly of unit B will be restrained from movement more than such closed gap distance, thereby preven ing unwanted closure or" its contacts under mechanical vibration and shock conditions or due to accidental electrical energization. The same will of course hold true in respect of unit A when the solenoid operating coil of unit B is energized.

We claim:

1. In a mechanical interlock for a pair of electromagnetic contactors which have solenoid operating plungers and contactor carrying plunger extensions mounted in opposed axial alinement, in combination, parts to be carried by an extension of one contactor, and parts to be carried by the extension of the other of said contactors which are laterally slipped into coaxial interlit inside certain of the first mentioned parts during mounting of said contactors to provide the aforementioned alinement thereof and which following such mounting of the contactors are relatively axially movable with respect to said first mentioned parts within limits established by the latter parts to restrict movement of the plunger and contactor assembly of one contactor when the solenoid operating coil of the other contactor is energized and vice versa.

2. A mechanical interlock in accordance with claim 1 wherein said first mentioned parts comprise a circular nut screwed on a threaded end portion of the extension of said one contactor and a collar having an internally threaded cylindrical portion screwed and non-rotatably secured on said nut, an integral cylindrical segment portion and aj washer secured to the latter portion adjacent its free end, and wherein the parts carried by the extension of said other of said contactors comprise a washer non-rotatably secured to the latter extension and coaxially disposed within said cylindrical segment portion of said collar between said nut and the first mentioned washer.

3. A mechanical interlock in accordance with claim 2 wherein said nut is non-rotatably secured on its plunger extension by a washer keyed on said extension and has a pair of lugs fitting into diametrically opposite recesses of a plurality of recesses spaced about said extension in said nut at equal rotary angles, wherein said nut also has a plurality of radial recesses formed in and spaced at equal rotary angles about its periphery, wherein said collar has a pair of elongated openings in its cylindrical portion spaced at a rotary angle corresponding to that between adjacent radial recesses of said nut, and wherein said nut and collar are non-rotatably secured together by a spring clip having ends projecting through said open ings in said collar into adjacent radial recesses of said nut.

4. A reversing type electromagnetic contactor comprising a pair of like units each of which has a housing comprising a closed end cup-shaped member and an enlarged cup-shaped member WhlClll'lflS a Wall joined with the side Walls of the first mentioned member in hermetically sealed relation and having an opening therein communicating with the interior of said first mentioned member, a solenoid operating assembly carried in said first mentioned member, stationary contacts mounted in said enlarged cup-shaped member and a movable contactor assembly carried on an extension of the plunger of said operating assembly within the last mentioned member, said units being disposed in axial alinement with the end edges of their enlarged cup-shaped members sectned together in a hermetically sealed joint, and a mechanical interlock acting to restrict movement of the solenoid plunger and contactor assembly of one unit when the operating coil or" the other unit is energized and vice versa, said interlock comprising parts carried by the extension of the plunger of one of said units and parts carried by the extension of the plunger of the other of said units coaxially disposed within certain of the first mentioned parts and axially movable relative thereto within limits. I

5. The combination according to claim 4 wherein said parts carried by said extension of the plunger of said one of said units comprises a circular nut screwed on a threaded end portion of said extension and non-rotatably secured in place, a collar having an internally threaded cylindrical portion screwed on and non-rotatably secured on said nut, an integral coaxial cylindrical segment portion and a washer secured on the latter portion adjacent its end, and wherein said parts carried by said extension of the plunger of the other of said units comprises a washer secured on the latter extension and coaxially disposed within said cylindrical segment portion of said collar for relative movement axially therewith within the aforementioned limit.

6; The claim according to claim 5 wherein the nut of said interlock has a plurality of like recesses formed in and spaced at equal rotary angles about its periphery, said collar has a pair of elongated openings in its Wall spaced at rotary angles corresponding to that between adjacent recesses of said nut and said collar andnut are non-rotatably secured to each other by a spring clip having ends projecting through said collar openings and fitting within adjacent recess openings in said nut.

References Cited in the file of this patent UNITED STATES PATENTS 

